Whats the recommended height above the ridge?

Hi folks

For installing anemometer on to a chimney, what is the recommended height for it to be please?
i.e. for there to be no or minimal turbulence effect?

Bashy,

Not sure what the minimum height is, I guess that will depend a lot on roof pitch and layout. Mine is on a 2.5m pole and it definitely suffers from turbulence at lower wind speeds. Problem is that the taller the pole the more wobble you get.

Paul

Thanks, my problem is, its on a bungalow, so thats a bit of a killer right there, i was hoping to go with about a 10ft pole from the stubby
chimney, but, been advised to go no more than a 6ft pole, still working on this idea as i didnt mention thats its just for an anemometer…

I have just found CWOP’s guide, they say optimal is 13ft (4m) above ridge 8O 7ft is the next on their list
Crikey, the only way would be using a 21 ft scaffold pole using 3 decent brackets on the gable end lol
I didnt bother with the 10m minimum, that aint gonna be possible whilst attached to the bungalow,
That will have to wait til i can afford another 10m mast, they’ve gone up in price since i last bought one
too :confused:

Mine is 12’ above the roof apex. I have a Windscope at 7’ and it does well there. Think they’re concerned with the ventury effect or eddies, close to the roof but at 7’ above the apex shouldn’t be an issue.

Thanks Skywatch, The aerial company i am in touch with are now saying (as it’s only the wind) that with an 8" mitre bracket
and lashing kit i can go with an 8’ pole on the chimney…

Might toy with the idea on the gable yet, nothing is ruled out…

Are you going to maintain it yourself? I found a gable mount is much more ‘accessible’ for me than a chimney, but it may be different on your bungalow.

I think with a bungalow maintenance would prob be about the same, the pitch of the roof makes it easy to traverse over
to the chimney, Im not sure of the height of the ridge, if its possible to get close to the 10m them i may do the gable mount
I would have liked to have done the 10ft on the chimney but they say its not say and 8 is max

I can’t remember if mine’s 8 or 10 foot pole on a chimney mount, but it’s stable and works fine. It’s been there in winds upto 98 mph and the gusts I record are normally within 5 mph of the UKMO station at Stornoway Airport, about 7 miles away.

is that OS cups still spinning Budgie?
my one I put up seized up within months

Cheers Martin hard to judge how high yours is, but also, aint that only a 6" mitre bracket?

They were the cups from my old WS2300 and they seized after about 6 months but I left them up there for a while. I actually found just the cups on the floor one morning after a storm, the wind was that strong it snapped the spindle!. :lol:

Simon, I got the bracket & pole as a kit from The WeatherShop about 7 years ago but I see they don’t do it any more. It’s larger than 6", more like 10 or 12". I found the band didn’t keep the bracket secure enough for up here so I drilled a couple of holes in it, through into the chimney, and put expanding bolts in to hold it.

Do you know how high you are in total, i.e. how close to the 10m are you?
If i remember right, the ridge of a standard house is 21ft?, if so then ya prob near as damn it…?

It must be about 10m from ground to anemometer but, as you’ve said, it’s the height above the ridge that counts.
There’s another station on the island with a Davis VP2 and he always reports wind speeds of 15-25 mph higher than me or EGPO during a storm. The station is on the northwest coast of the island so you can expect the winds to be stronger but he’s even beaten Carngorm Summit on occasions! I’m sure he has something effecting his anemometer that gives these anomalies but I’m not sure what it is as I don’t know where his station is mounted.

It could be that he has an obstruction such as a tree and hes set an offset to counter this, perhaps a bit too much?

the higher you get, the more risk of thunder struck in the pole…?

Nah thunder ain’t the problem, lightning might be though :wink: there is a tree about 50 away that’s higher so here’s hoping… I have put in for a preliminary assessment…

Preliminary says i have to apply for permission, of course i do else they wouldnt make any money, going to
ring them to see what is possible without permission, i.e. on the gable end and at what height…

Just to come back to this, re planning, if its below 4m from the ground and i think its 10m from the neighbours then
thats ok as long as you say its a weather vane, do not say its anything else as they do not have a guideline for an]
anemometer so then planning will be needed over

Hi Bashy as for fixings etc. you could try here or here & here mine is about 7/8foot above the ridge hope this helps.

teal.


By far, the easiest way I’ve found it to use one of these gable mounts:

http://www.amazon.com/Winegard-SW-0012-Gable-Mount-Antenna/dp/B001DFTGUQ?ie=UTF8&keywords=gable%20mount&qid=1459190570&ref_=sr_1_2&sr=8-2